Feedback Inhibition of DszC, a Crucial Enzyme for Crude Oil Biodessulfurization

The Rhodococcus erythropolis (strain IGTS8) bacterium has a tremendous industrial interest as it can remove sulfur from crude oil through its four-enzyme (DszA-D) 4S metabolic pathway. DszC is one of the rate-limiting enzymes pathway and that most suffers feedback inhibition. We have combined molecular docking dynamics simulations to identify binding sites which two products pathway, 2-hydroxybiphenyl 2′-hydroxybiphenyl-2-sulfinate, induce identified four potential sites: adjacent close 280–295 lid loop proposed contribute oligomerization proper flavin mononucleotide cofactor, other active site substrate site. By considering (i) occupancy (ii) similar inhibitor poses, we propose mechanism inhibition occurs disturbance consequent due weakening interactions between loop, both 131–142 C-terminal tail. Nevertheless, or also compromises critical within DszC. disclosed details provide valuable insight for future rational enzyme engineering protocols develop mutants more resistant against observed mechanism.